In video distribution systems, decoding equipment may receive a video stream comprising audio and video data for presenting a corresponding program. The data for each program may be encoded in a format, such as Motion Picture Entertainment Group 2 or 4 (MPEG-2 or MPEG-4), in which intra-coded frames may occur at fixed maximum intervals in the stream, known as the Group Of Pictures (GOP) interval. Other frames, known as B-frames and P-frames, may carry only those portions of an individual video frame that differ from a previous and/or subsequent video frame in order to reduce the size of the data that is transmitted for that frame. In conventional systems, the bandwidth required to transmit these frames may be difficult to predict or estimate, however, leading to inefficient allocations of bandwidth in excess of that required. Furthermore, a shortage of bandwidth can lead to noticeable transmission delays and/or errors in the video data, thus degrading a viewer's experience.